From Ewan Roy in Succession to Sideshow Bob in The Simpsons, here are 15 truly unforgettable characters who elevated their shows – when they eventually turned up

Mike Hannigan was the only character to truly feel like a seventh Friend. He was the perfect match for Phoebe, a lightning rod for her kookiness and providing the solid family she’d never had. It wasn’t just the fact that he was played by Paul Rudd that managed to win over the viewers. His profile was nowhere near what it would later become, so the audience weren’t responding to star power in the same way they had, say, to Bruce Willis, Tom Selleck or Reese Witherspoon. Mike had to play the long game, put in the graft and win Phoebe’s trust, and won ours in the process. AJ, London

If it counts as late, with his arrival in episode five of the first season of Succession, my vote goes to Ewan Roy, elder brother of Logan, played impeccably by James Cromwell. An agitator to his ruthless younger brother, Ewan with his social and political conscience gave left-leaning viewers someone to root for. Ann, London

Winston was already a brilliant character, and adding in a love interest for him in season four was such a great decision. Aly was smart, funny and a perfect partner for Winston. On top of all that, she gelled so well with the extremely strong ensemble cast, it made you forget she wasn’t there from the beginning. Aimee, Ulverston, Cumbria